A device using an energetic electron beam from a carbon nanotube electron emitter has been developed to generate plasmas at pressures near or below atmospheric. The low-pressure electron source region (10-6 mbar) and the higher pressure (up to 1 atmosphere) plasma generation region are separated by a 300 nm SiN x window/membrane. The energy of the electron beam is of the order of 10 kV with a current of 10 μA prior to passing through the window, with nearly 85% of the beam passing through the window to the plasma generation region with a 10% loss in energy. The device could be operated in one of two modes, closed or opened. Closed mode operation has been used to generate excimer emissions from XeI∗ and XeCl∗ at 253 nm and 308 nm, respectively, at pressures below atmospheric. Ambient air has been used in the open mode operation with and without a flow of argon or helium across the SiN x window. Optical emission spectroscopy revealed that the open mode operation yielded a variation of excited state species that was found to be dependent on the electron beam energy and the neutral gas flow in the reaction region.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- electron beam
- plasma source